Art of making cementitious products



A. 0. CROZIER.

ART OF MAKING CEMENTITIOUS PRODUCTS.

APPLICATION FILED MAR-22,1918- Patented Jan. 17, 1922.

Z 0 I. w e U n a UNITED STATES PATENT OFFICE.

ALFRED OWEN GROZIER,- OF NEW YORK,v N. Y.

ART OF MAKING QEHENTITIOUS PRODUCTS.

To all whom it may concern:

Be it known that I, ALFRED OWEN CRoz- IER, a citizen of the United States, residing at New York, county and State of New I York, have invented certain new and useful removed from one end of a, moist unset cementitious column. The chief object of the present invention is to provide a process which will produce articles or products of high quality rapidly and economically.

-Another object is to provide a process in which a slushy cementitious mixture, that is, a mixture containing water in' excess of the amount needed for hydration of the ocment, or other cementitious substance, is compacted partly by the pressure of its own weight and partly by pressure from anexternal source, exerted as the portion from which the articles are to be made is severed from the column." Another object is to proviole a process in which the column is subjected to successive impacts or concussions thereby aiding in the desired compacting of the material.-- A further object is to pro vide a process in which at. least. one surface of the severed and removed portion of the column is given a characteristic texture, so to speak, distinctive from that produced by processes or machines in which the bricks or other articles are cast or molded in forms. To these and other ends the invention consists in the novel steps hereinafter de scribed. g

In carrying out my improved process or -method in the preferred manner the mate rial I emplgy is a cementitious mixture, for example sand and cement, of a sloppy or slushy consistency, that is to say, containing an amount of Water in excess of that needed for the desired hydration of themment. This consistency of the concrete. minimizes the entrapplng of air in the mass and the consequent formation of air bubbles,

void spaces or cavities, therein, and enables me, by subsequent, treatment, to practically Specification of Letters Patent. Patented J an 17, 1922 Application filed March 22, 1918. SeriaI'No. 224,046. I

eliminate any air bubbles, void spaces or cavities that may be formed.

The cementitious material of the consistency indicated is erected or formed into a vertical column, in an upright tubular shaft or trunk. In this form the difference in the specific gravities of the water and the solid constituents causes the latter to smk and the excess water, to rise in the column, thus aiding in the attainment of an efi'ective un-Watering of the lower portion of the column. Moreover, the water has a marked lubricating effect, enabling the sand, particles to slide or move more freely upon or past each other and thus fit themselves together more closely and compactly This gives greater firmness, solidity andstrength to the mass. At the same time the lower portion is compacted by the welght of the superincumbent mass. The extent of the compacting thus efi'ected, depends, in general, upon the height of the column and maybe such as to give such lower portion practically the maximum density that can be attained in a cementi-. tious mixture, but according to the preferred form of the present invention the height of the column is such that the density of itslower portion, due to the weight and compacting or concentrating eflwt of the portions above, is not only less than the aforesaid maximum density but is indeed substantially less than desired in the articles which are to be formed from said lower portion. The additional densifying is effected in the process of severing or removing such lower portion or parts thereof for formation into the bricks, blocks, or other desired articles, or it may be efiected in the process of subdividing the severed. portion of the column, or partly in each.

The severin of the lower portion of the column, and preferably) more or less of the desired or necessary additional compacting thereof,'are eflected by forcing or drivi 100 above its bottom a blade or knife of suitable ing into the column at a proper distance the bottom of the column; and in the second place, as will be explained more-fully. her

inafter, it may exert" a powerful downward pressure on the severed ortion or the portion being severed, thereby giving the same the additional compactness necessary or desirable at this stage.

The severed lower ortion of the column may now be removed y lowering the pallet or other base on WlllCh the column was formed, leaving the up er part of the column resting on the kni e; but in practice I prefer to follow the severing knife (which is horizontal) with one or more vertical knives which subdivided the severed portion in vertical planes and at the same time exert more or less lateral pressure on the subdivisions, thereby attaining further densifying or compacting of the same.

The subdividing knife or knives are now retracted to free them from the column, but the upper portion of the column is left reston the severing knife. The pallet or ot er member on which the severed lower portion of the column rests is now lowered, and carried away with the article or arti-" cles formed thereon as above described.

hours or even days.

Upon removal of the articles from the pallet the latter can be replaced, but I prefer to leave the articles on the original pallet'during at least a part of the time of hardening or setting of the cementitious material, in which case a fresh pallet is placed in position below the column. The severing knife is now withdrawn, preferably as rapidly as possible. The entire column then falls practically as a whole, and strikes the I pallet with sudden force. The heavy impact thus produced is an importantaid in compacting the material that now becomes the lower portion of the column, and under favorable conditions may be sufiicient topermit a further reduction of the total height of the column.

The operations or steps ,described above are now repeated, it being understood that during the progress of thework fresh mate'rial of the proper consistency is added to the top of the column to compensate. for the removals from the bottom, the additions bemg made preferably before retraction of the sever-mg knife so that the mass of the added material will mcrease the forceof the blow or concussion when the column is allowed to ratusas are, ordinarily, essential to the' practice of the invention in an eflicient manner; omitting entirely, for the sake of simplicity and clearness of illustration, the elements or mechanisms for actuating the few moving members or parts of the apparatus.

Referring now to the accompanying drawing,

Fig. 1 is a front view of a vertical shaft or container in which the cementitious column may be formed.

4 Fig. 2 is a section on line 2-'-2 of- Fig. 1, looking in the direction of the arrows and showing also the severing and subdividing knives in positionto enter the column at thebottom thereof.

Fig. 3 is a-seetion on line 3-3 of Fig. 2,

lookingin the direction of the arrows.

Fig. 4 is a perspective view showing the pallet and the articles (in the present .in-

stance bricks) formed'on the pallet by severing and subdividing the lower portion of the column.

Fig. @is a view similar to 4 showing only a single article on the pallet, produced by severing and removing but not subdividing the lower portion of the column. Figs. 5, 6,7 and 8 are-fragmentary side views of the severing knife, showing different forms of the cutting edge thereof.

In using my invention for making brick,

the upright hollow shaft 110, in which the column of slushy concrete or cementitious material is formed, is preferably constructed to provide a columnabout twenty- I four inches wide and-about eight inches thick, at the base. The shaft is preferably constructed with rigid or inflexible air and water-tight walls, and is closed at the bottom by a removable abutment, as a plate or pallet 11, supported by a vertically movable table 12. a

At a proper distance from the bottom (in the present instance, for making brick, the distance is about four. inches) the shaft is provided at front and back with horizontal slots 13, 14, to receive the horizontal sever Instead of providing mere ing knife 15. v slots for the horizontal knife the part of the shaft below the path of the knife can be'made removable, as a whole or in sections. Vertical slots 16 .(opening at the top into said horizontal slots) are provided to receive the vertical subdividing knives 17.

The number and spacingof the subdividing knives depends of course u on the size I which it is desired that the articles formed thereby shall have. In making brick from a column twenty-four inches wide I use, ordinarily, nine subdividing knives, spaced equidistantly from each other. Preferably the vertical knives are rigidly attached to the horizontal knife with their forward or cutting edges back of the cutting edge of the horizontal knife a distance which is slightly greater than the thickness of the column at the base.

The shaft contains slush concrete, thereby forming a vertical column of the latter which has its lower portion unwatered and partially compacted as described hereinbefore.

The column being thus established, the

horizontal severing knife 15 is driven or forced into the lower/portion through slot 13 and out through slot l hrthereby completely separating the lowermost part of the column from the upper part. Preferably the knife is of material thickness, sayabout one-half inch, so that its introduction into the column may effect the desired additional compacting or densifying. Preferably the cutting edge of the knife is beveled. If the bevel is equal on both sides, as in Fig. 2, the compacting effect is divided with substantial equality between the parts of the column below the knife and adjacent to and above the knife. With the bevel entirely on the bottom, as in Fig. 5, the compacting action is expended entirely upon the severed portion of the column, and with the bevel entirely on the top as in Fig. 6 no compacting effect is produced upon the severed portion; whereas with 'one side beveled more than the other, as in Fig. 7 for example, the compacting effect will be greater toward that side having the greater bevel. In this way it is possible to distribute the compacting effect in the most advantageous mann'er,'as experience may indicate, with due regard to the height of the severed portion. The compacting effect exerted upwardly by the knife is also influenced by the inward slant of the sides of the shaft, making it, in general, impossible for the knife to lift the whole column, with the result that the layer of material above the knife is lifted by the latter into a space of less horizontal cross-sectional area, thereby causing the outer portions of such layer to be crowded inwardly. Thus the said layer of material is in effect subjected to; pressure onall six sides,on its bottom by the knife directly,

on its top by the weight of the mass above,

and on its sldes by the tapering shaft,

I The movement of thehorizontal knife being continued, the vertical subdividing knives 17-now pass into the vertical slots 16, throughthe severed portion of the column, and out' through the corresponding slots in the rear wall of the shaft, thereby dividing the aforesaid severed portion-into bricks, in

the present instance ten in number, there The knives 15 and 17 are now withdrawn 1 until the latter are clear of the column. These movements of the knives have an advantageous trowelling effect, giving smoothly finished surfaces and edges.

The lower portion of the column having been thus severed and trowelled, the knives are arrested with the forward part of the horizontal knife still extending, through the column. The table 12 and pallet 11 are then lowered, thus withdrawing the severed and subdividedlower portion of the column downwardly therefrom. The material being in close contact with the underside of the knife and at the same time wet and more or less plastic, the bricks tend to adhere to the knife, and hence as they are freed from the latter their upper faces cling momentarily and numerous small projections, more'or less pointed, are thus drawn out as the surface of the bricks breaks away from'the knife.

pleasing and the pattern does not repeat as is the case with blocks or bricks whose rough sides are produced by the configurations of the mold in which they are cast. However, a smooth trowelled face can be obtained if desired, by using a severingknife with the underside'of its forward port-ion cut away, as in Fig. 8 for example, so that the bricks are not in contact with the knife when they are lowered out of the shaft.

The bricks are now removed from the pallet and the latter replaced, or, preferably, the bricks are left on the pallet on which they are formed and a fresh pallet to close the bottom of the shaft is placed on the table .12, which is then raised. The

severing knife is now suddenly withdrawn, thus allowing the entire column to drop bodily upon the fresh pallet. As alreadyother portions of the column; so that what is at any given time) the very top of'the column, receives in its descent through the shaft a succession of such compacting shocks, each time with more material, and

' hence greater weight, above it.

by the lubricating presence 0 "withdrawal of the horizontal support or knife 15, the column falls into a space largerthan it has previously occupied, spreading out and filling the same, causing the instant rearrangement of the particles, throughout the entire mass, with reference to each other, this effect being markedl facilitated the excess water. This is especially true of the part above the horizontal slots if below the latter there is no flare, or less flare, than above. The result is a marked tendency to produce cracks between the column and the walls of the. shaft enclosing the same, and since air cannot reach the cracks from, the outer autmosphere the partial vacuum in the cracks can be relieved only by inflow of material from the, column. Waterand air being lighter and more mobile than sand, water and air bubbles rather than sand are sucked into the cracks, thus, aiding in; the desired unwatering a'nd.unairing of the slushy mixture. i g

The operations described above are repeated, it being understood that fresh material isadded at the top of the column, continuously or :at intervals, to compensate for the repeated withdrawali from the bottom. The process is in effect continuous, as the formation and removal of the articles from the lower portion of the column, though intermittent, occurs at regular intervals and there is no. stoppage 'for recharging theshaft or magazine. The process is also rapid, it being easily possibleto make with eachapparatus two hundred or more pallet-loads of brick per. hour, or

' say twenty thousand bricks per. working day of \ten hours.

Moreover, the "bricks when severed still contain ample water throughout for complete hydration of the cement and hence the cementitlous properties of the latter are fully developed.

It is to be understood that the invention is not limited to the specific procedure and apparatus herein described,' but can be torn its spirit as claims.

Iclaimz- 1. In the art of mak ng cementitious are,

defined by the fo lowing pact aidsin' densifying the lower part of of material [of slushy. concrete of a height sufficient to ractlced in other ways without de arture ticles. in which successive sections are removed from the bottom of a concrete column, the steps comprising establishing in an upright hollow shaft or container a column of slushy concrete of a height sufficient to cause its own weight to effect a substantial compacting of its lower portion; 'compressing the lower portion only of the column while such portion is still 'in' the shaft to further compact or densify such portion and severing a section from the bottom of the column; removing the severed section and permitting the remaining portion of the column to descend; and maintaining the height of the column by the addition of concrete to the upper part thereof.

2. In the art of making cementitious articles in which successive sections are removed from the bottom of a concrete column, the steps comprising establishing in an upright hollow shaft or container a column of slushy concrete of a height suflicient to cause its own weight to effect a substantial compactingof its lower portion; compressing the lower portion only of the column while such portion is still in the shaft to further compact. or densify such portion,- and severing a section from the bottom of the column; removing the, severed section and permitting the remaining portion of the column to descend suddenly by its own weight upon a removable abutment closin the bottom of the shaft whereby the resu ting imthe column; and maintaining the height of the column by the addition of concrete to the u per part thereof; a

3. fns'the-art of making cementitious articles in which successive sections are removed'from the bottom of a concrete column, the-steps comprising establishing in an uprighthollow shaft or container a column of slushy concrete of a height suflicient to cause its own weight to effect a substantial compacting of its lower portion; passinga severing knife of' suitable thickness into the unset lowerportion of the column to further compact or densify at least a part of such portion and sever a section from the moved from the bottom of a concrete col umn, the steps comprising establishing 1n an,

upright'hollow shaft or container a column pactor densify such portion and severe H0 section from the bottom of the column; removing the severed section and withdrawing the knife suddenly to permit the column to fall upon a removable abutment closing the bottom of the shaft whereby the resulting impact aids in densifying the lower portion of the column; and maintaining the height of the clumn by the addition of concrete to the upper part thereof.

5. In the art of making cementitious articles in which successive sections are removed from the bottom of a-concrete column, the steps comprising establishing in an upright hollow shaft or container a column of slushy concrete of a height sufiicient to cause its own weight to effect a substantial compacting of its lower portion; passing a severing knife and one or more subdividing knives of suitable thickness into the unset lower portion of the column while the same is still in the shaft to further compact or densify such portion and to sever and subdivide the part below the severing knife; removing the severed and subdivided section of the column and withdrawing the knives to permit the column to descend; and maintaining the height of the column by the addition of concrete to the upper part thereof.

6. In theart of making cementitious articles in which successive sections are removed from thebottom of a concrete column, the steps comprising establishing in an upright hollow shaft or container a column of slushy concrete of a height sufficient to cause it to descend through the shaft by its own weight and effect a substantial compacting of its lower portion; compressing the lower portion only of the column while such portion is still in the shaft to further compact or densify such portion and severing and subdividing the lowermost section of the column; removing the severed and subdivided section and permitting the re-,. maining portion of the column to descend; and maintaining the height of the column by the addition of concrete to the upper part thereof.

7. In the art of making cementitious products in which portions of an upright slushy cementitious column are successively removed from the bottom thereof, the steps comprising passing a severing knife into the lower portion of the column to sever the part below the knife. and'lowering the severed part out of contact with the knife whereby a multiplicity of relatively small projections are drawn out on the more or less plastic surface as the same separates from the knife.

8. In the art of making cementitious products in which portions of an upright slushy cementitious column are successively removed from the bottom thereof, the steps comprising passing a severing knife and one ucts, in which portions of an upright slushy cementitious column are successively removed from the bottom thereof, the. steps comprising passing a horizontal severing knife into the lower portion ofthe column to sever the lowermost part thereof and passing into such lowermost part one or more vertical subdividing knives to subdivide the said-part in vertical planes, re-' tracting theknife or knives out of said lowermost part whereby the faces of the subdivisions thereof are trowelled by the surfaces of the knife or knives, and then lowering the said subdivisions out of contact with the horizontal severin k nife whereby a multiplicityof relative y small projections are drawn out on themore or less plastic upper surfaces of the subdivisions as the same are separated from the under surface of the knife.

.10. In the art of making cementitious articles in which successive sections are removed from the bottom of a concrete column, the steps comprising establishing in an upright hollow shaft or container a column of slushy concrete of a height sufficient to cause its own weight to effect a substantial compacting of its lower portion; passing a severing knife into the unset lower portion of the column to further compact or densify such portion and sever therefrom the part below the knife; removing the severed section of the column downwardly out of the shaft and out of contact with the knife whereby the adhering upper surface of the severed section is roughened as described;

ing of its lower portion, passing a severing member through said lower ortion of the column while maintainingjsaid portion sta-' I tionary, subdivlding said portion 1n vertical planes while it is still imprisoned, and removing the subdivisions.

In testimony whereof I hereunto aflix my signature.

ALFRED OWEN CROZIERJ 

